1CM60_0E
Products: R&S CMU300, R&S ROMES
Optimization of HSDPA networks
with the Radio Communication Tester R&S® CMU300
and Coverage Measurement System R&S® ROMES
Application Note
The Radio Communication Tester R&S CMU300 and Coverage Measurement System R&S ROMES
provide a wide range of possibilities to check the HSDPA air interface and network quality. The
measurement results that can be obtained with the aforementioned solutions ensure flawless operation of
HSDPA services from the start and longstanding customer acceptance of the new technology.
All rights reserved – 1SPV/CF 1CMP/Gr 02/2006 – 1CM60_E.doc Version V1.00
HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
Contents
1 Introduction.......................................................................................... 2
2 Testing HSDPA Node Bs with the R&S CMU300 ................................. 4
Realtime HS-SCCH Monitoring ....................................................... 4
Realtime Cell Throughput Measurement ......................................... 6
Realtime BCH Monitoring ............................................................... 7
Checking Physical Transmission Parameters.................................. 8
Tips for Practical Use.................................................................... 10
3 Measurements in HSDPA Networks with R&S ROMES...................... 13
R&S ROMES Hardware Configuration for HSDPA ........................ 13
HSDPA-Specific Information in R&S ROMES ............................... 15
Coverage Measurements.............................................................. 24
Quality of Service Measurements ................................................. 26
4 References ........................................................................................ 27
5 Abbreviations..................................................................................... 27
6 Ordering Information.......................................................................... 29
1 Introduction
The introduction of HSDPA confronts the entire industry with enormous
challenges. All network operators must ensure complete availability of
services by skillfully planning their networks, and must decide which parts
of the network they should upgrade first with HSDPA. Future HSDPA users
must share resources with other UMTS users. It is therefore important to
develop a strategy as to how much network capacity should be available to
these HSDPA users. HSDPA contains an extensive protocol on the air
interface and offers many possibilities for parameterization. To optimally
support the desired services, every network operator must customize this
parameterization.
Test and measurement solutions for user equipment (UE) and networks
significantly help to ensure that the introduction of HSDPA runs smoothly.
Besides the intensive testing of UE, intensive tests for the introduction of
HSDPA are required in the network itself. Rohde & Schwarz offers a wide
range of T&M equipment to ensure that HSDPA is rolled out on schedule.
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The R&S CMU300 base station tester allows you to conduct HSDPA
throughput measurements that make it possible to evaluate and optimize
the algorithms for assigning resources. The tester can also be used to
check HSDPA-specific settings on Node B and to perform measurements
on the physical HSDPA channels.
R&S CMU300 base station tester
R&S Coverage Measurement System ROMES supports HSDPA network
setup and radio network optimization. Extensive coverage measurements
can be performed during a drive test. The network operator obtains
information about the availability and parameterization of the HSDPA
services at different locations within the network. The measurements
provide information regarding the actual HSDPA configuration, the
signaling and the data rates achieved on different levels. An end-to-end
application is set up for this purpose and evaluated during the drive test.
The network operator gains valuable information on how to further improve
HSDPA coverage and the quality of service. These measurements can be
configured in parallel to UMTS and GSM measurements to provide an
overall picture of the network.
Coverage Measurement System R&S ROMES
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2 Testing HSDPA Node Bs with the R&S CMU300
Realtime HS-SCCH Monitoring
The high-speed shared control channel (HS-SCCH) is important for
communication in HSDPA mode. It transfers information about the nature
of the following data channel (HS-PDSCH) as well as information
indicating which UE the data packet is specified for. The information
applies to the following:
Channelization code set
Modulation scheme
Transport block size
HARQ process
Redundancy and constellation
New data indicator
UE ID
Several HS-SCCHs may be transmitted simultaneously. The
R&S CMU300 thus not only monitors the HS-SCCHs but also analyzes
whether the communication in HSDPA mode is taking place correctly.
RNC
UE1
Transmitter
Line
Interface
UE2
CPICH / BCH
Synchronization
...
Radio (TRX)
HS-SCCH
Monitoring
UE128
Receiver
Signaling Receiver
(Demodulator, FEC, Data
Analyzer)
UE Set
Node B
Indication of 4 HS-SCCHs
Troughput Calculation
R&S CMU300
Setup for HSDPA monitoring and throughput measurements
The R&S CMU300 can simultaneously monitor up to four HS-SCCH
channels. The code channels to be monitored can be selected by the user.
Moreover, the R&S CMU300 can detect up to 128 different UE IDs. The
UE IDs to be detected can be determined by means of a list or an
automatic scan routine (UE ID Scan). The information of the detected
HS-SCCHs is displayed directly on the R&S CMU300’s user interface as
follows:
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Detail
information
screen of the
selected UE ID
HS-SCCH
monitor with
scheduling
information (here
with three active
HS-SCCHs)
HS-SCCH monitoring GUI
The HS-SCCH information measurement can be performed after
successful CPICH/BCH synchronization in different modes:
Start mode
UE ID Scan:
Capturing starts when a predefined number of
active UEs are detected.
Start Immediate:
Capturing starts right after the user starts the
measurement.
Start at HSFN:
Capturing starts when the specified start HSFN is
reached.
Start at UE ID:
Capturing starts when the specified start UE ID is
detected the first time.
Repetition mode
Single Shot:
The measurement is stopped after 1024 HSFNs
are captured (depending on display mode).
Continuous:
Continuous capturing of
data until the
measurement is explicitly stopped by the user.
Display mode
Result Table vs. HSFN: The monitored HSFNs are displayed continuously.
Result Table vs. UE ID: Only HSFNs containing data are displayed.
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Realtime Cell Throughput Measurement
The Cell Throughput application measures the HS-PDSCH data rate and
throughput by analyzing the HS-SCCH information. Up to four HS-SCCHs
and 128 different UE IDs can be monitored and displayed in realtime. The
UE IDs to be detected can be determined by means of a list or an
automatic scan routine (UE ID Scan). For each monitored UE ID, the
current throughput, the average throughput and the maximum/minimum
values are analyzed. By evaluating the new data indicator flag, data rate
and throughput are differentiated and displayed.
The throughput measurement can be performed after successful
CPCIH/BCH synchronization in different modes:
Start mode
UE ID Scan:
Capturing starts when a predefined number of
active UEs are detected.
Start Immediate:
The throughput measurement starts right after you
press the Start button.
Start at HSFN:
The measurement starts when the specified Start
HSFN is reached.
Start at UE ID:
The measurement starts when the specified Start
UE ID is detected for the first time.
Repetition mode
Single Shot:
The measurement is stopped after a specific
number of subframes (max. 20479).
Continuous:
Continuous capturing of
data until the
measurement is explicitly stopped by the user.
Display mode
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Current:
Data rate and throughput of the current HSFN are
displayed.
Average
Average results are calculated over a specified
number of subframes.
Max / Min
Max/Min results are recorded over the whole
measurement time.
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Bargraph of UEs to
be monitored:
blue: data rate;
green: throughput;
red: selected
Detailed
measurement
results including
statistical
evaluation
Selection of a
UE ID
Cell throughput measurement GUI
The bar graph shows a rough overview of all UEs to be monitored.
Depending on the display mode, the bar graph shows current, average,
minimum or maximum values. The present display mode is shown in the
upper right corner of the screen. The different colors of the bars show the
data rate and throughput. To show detailed measurement values, a UE-ID
index can be selected. The selected UE-ID index is marked red in the bar
graph and the corresponding UE-ID is displayed. The display mode and
the UE-ID for detailed measurement results can be selected during the
measurement as well as after the measurement is stopped.
Realtime BCH Monitoring
The BCH monitoring function of the R&S CMU300 signaling mode
provides a convenient means of performing online analysis of the system
information blocks (SIBs).
Indication of
SIBs received
Content of the
selected SIB
(here SIB 11)
BCH monitoring GUI
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Checking Physical Transmission Parameters
The following measurements of static code channel combinations can be
performed with the R&S CMU300:
Power measurement:
BTS output power
Modulation analysis:
Error vector magnitude (EVM) including magnitude error and phase error
IQ origin offset
IQ imbalance
Carrier frequency error
Waveform quality
Spectrum analysis:
Occupied bandwidth (OBW)
Spectrum emission mask (SEM)
Adjacent channel leakage ratio (ACLR)
Code domain measurements:
Code domain power (CDP)
Peak code domain error power (PCDEP)
Code domain
with active code
channels (here
4xHS-SCCH and
5xHS-PDSCH)
Time domain
with code power
of the selected
code channel
(here
HS-PDSCH code
number 3)
HSDPA code domain power measurement GUI
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Indication of
modulation
quality
parameters
including
statistical
evaluation
HSDPA modulation analysis GUI
Selection of
signal to be
analyzed (here
TM5 with 14
DPCHs and four
HS-PDSCHs)
The R&S CMU300 is able to analyze and measure the following static
WCDMA TX signals (applies primarily to modulation analysis and code
domain measurements):
-
Conformance measurements in accordance with the 3GPP TS25.141
FDD R5 specification on the basis of predefined channel combinations
(test models 1 to 5).
-
Customer-specific preconfigured downlink channel combinations (table
form) for frequently repeating test scenarios.
-
The auto-channel detection mode makes it easy to test unknown static
WCDMA signals. This mode automatically analyzes and measures the
existing WCDMA channel combination.
For the R&S CMU300, it is irrelevant which Node B controller was used to
activate the TX signal to be measured. All standard-compliant static
WCDMA/HSDPA signals generated by an RNC or special Node B
controller can be analyzed.
Measurement
Maximum output power
CPICH power accuracy
Frequency error
Power control dynamic range
Total power dynamic range
Occupied bandwidth
Spectrum emission mask
Adjacent channel leakage ratio
Error vector magnitude
Peak code domain error power
Supported by the R&S CMU300
√
√
√
√
√
√
√
√
√
√
TX measurements of UMTS specification 3GPP TS 25.141 FDD Release 5
supported by R&S CMU300
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Tips for Practical Use
Connection to the base station
The R&S CMU300's flexible RF interface allows the instrument to be
adapted to a variety of test environments:
RF1 input:
Direct connection of BTS antenna output
with powers of up to 47 dBm CW possible
(53 dBm PEP)
RF4 IN input:
Sensitive test input for peak powers of up
to 0 dBm (PEP)
R&S CMU300 front panel, RF interface
The sensitive RF4 IN input allows you to test base stations that are in
active operation as follows:
-
Direct measurement of transmission parameters via heavily attenuated
TX monitor outputs
-
OFF AIR HSDPA measurements with line of sight to the BTS.
The RF input of the R&S CMU300 and the drive level must be selected to
match the previously known maximum transmitting power. It is advisable
to drive the instrument manually (via the Connection Control / Analyzer /
Expected Power Mode / Manual menu); the R&S CMU300 input level to be
expected should be set 5 dB above the maximum PEP to be expected
(Expected Power: PEP + 5 dB).
The R&S CMU300 can be connected to the reference frequency of the
base station via a BNC input on the instrument's rear panel. This will
eliminate test results corrupted by reference frequency offset. In addition,
the instrument can be equipped with an OCXO (R&S CMU-B12 option).
Additional information regarding transmitter measurements
Physical transmitter measurements are performed mainly in the
R&S CMU300 non-signaling mode; the common pilot channel (CPICH) in
the channel combination to be tested must be activated. The scrambling
code and the channel of the transmitter to be measured must be known in
advance and entered in the Connection Control / BS Signal menu.
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Additional information regarding HSDPA monitoring and throughput
All realtime measurement functions are performed in the R&S CMU300
signaling mode. This mode is based on a downlink receiver (FEC), where
the instrument synchronizes like a UE to the cell (CPICH and BCH),
(Connection Control / Connection / Softkey Start Sync. menu).
Connection Control / Node-B Sig. / Node-B Settings menu
The scrambling code and the channel of the cell to be measured must be
known in advance and entered in the Connection Control / Node-B Sig.
menu.
Connection Control / Node-B Sig. / HSDPA Channels menu
The number of HS-SCCHs used in the cell and their channel codes can be
entered further down in the same menu. The Code Domain Power
measurement menu makes it easier in most cases to determine the
HS-SCCH parameters.
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Number of UEs
to be observed
(max. 128)
UE ID Index
table
Cell Throughput / UE Configuration GUI
The number of UEs to be observed and their UE-IDs are taken into
account as follows:
-
If these parameters are known, they can be entered in the UE ID Index
table.
-
The UE ID Scan function scans in active operation specifically for
HSDPA radio bearers; i.e. prior to the actual HS-SCCH analysis,
active UE IDs are automatically detected and copied to the UE ID
Index table.
Activation of the
UE ID Scan
function via the
start mode
HS-SCCH monitor GUI
In addition to the aforementioned HSDPA analysis functions, the
instrument can simulate an HSDPA UE in the uplink. For this purpose,
configurable ACK / NACK / CQI sequences are provided (R&S CMU-K73
option).
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3 Measurements in HSDPA Networks with R&S ROMES
R&S ROMES Hardware Configuration for HSDPA
In comparison to the R&S CMU300 base station tester, the R&S ROMES
coverage measurement system is designed for performing mobile phone
measurements during drive tests.
Typically an R&S ROMES coverage measurement system consists of a
laptop or PC running Windows XP Professional and the R&S ROMES
software.
The R&S ROMES coverage measurement software is used for the
following purposes:
-
To define test devices
-
To set up measurement tasks
-
To acquire and store measurement data
-
To display measurement results in realtime during the drive test
In addition, a replay function is included for replaying the drive test using
similar or different display options in realtime or with adapted speed.
Measurement data can also be exported in ASCII or other formats.
As test devices, one or more test mobile phones or data cards and one or
more scanners are connected to the R&S ROMES laptop or PC.
Depending on the customer-specific requirements, the system may be
used in different installations and environments, such as the following:
-
In a rugged case, incl. laptop, scanner and mobile phones
-
In a specially designed backpack incl. battery power management
-
In a fixed 19" rack installation (e.g. inside a measurement vehicle)
Examples of coverage measurement system installation
For performing tests in HSDPA networks, the following minimum
requirements are necessary:
-
R&S ROMES 3.52 or later
R&S ROMES 3.52 requires a PC with at least either Pentium M or
Pentium IV 3GHz processor, min. 1 GB RAM and Windows XP
Professional.
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R&S ROMES drivers R&S
R&S ROMES-UM4 (HSDPA)
-
HSDPA-capable test mobile phone(s) or data card(s), compatible with
R&S ROMES
13
ROMES-UM1
(WCDMA)
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The only chipset currently supported for HSDPA measurements is the
Qualcomm MSM6275. To connect a device with this chipset to R&S
ROMES, direct access to the Qualcomm interface is required.
Currently supported devices are Qualcomm's TM6275 test mobile phone
and Option's GlobeTrotter Fusion+ (HSDPA-ready) data card.
Currently supported HSDPA devices
In future, several mobile phones and data cards are expected to be based
on this chipset. Rohde & Schwarz will phase in the development of the
necessary drivers in order for R&S ROMES to support these devices.
Further (non-HSDPA-specific) important information about WCDMA
networks may be gained by using the R&S TSMU radio network analyzer
in parallel to the HSDPA devices.
Although no HSDPA-specific logical channels are measured by the
R&S TSMU, the recorded information is crucial for the optimization of the
HSDPA networks. For example, the CQI uplink response of the HSDPA
UE in the HS-DPCCH is directly related to the CPICH, which is measured
by the R&S TSMU. Radio environment conditions have a direct impact on
the data rates achieved.
R&S TSMU radio network analyzer
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For further details regarding the R&S TSMU, please see references [4] and
[5].
HSDPA-Specific Information in R&S ROMES
To receive specific information about HSDPA-related parameters, Rohde
& Schwarz has introduced the following HSDPA dedicated views into the
R&S ROMES software:
The HSDPA Configuration View provides a general overview of the
HSDPA configuration:
Downlink highspeed channel
information
Uplink HSDPCCH channel
information
HS-SCCH channel
information
Basic HARQ
information
UMTS HSDPA Configuration View
Most of the displayed information is mobile phone-specific and primarily
intended for monitoring the status of the test mobile phone.
The high data rates in the downlink require steady feedback about the
radio link situation from the mobile phone to the Node B. All uplink
information is summarized conveniently in one window, the HSDPA
Uplink HS DPCCH View.
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DTX
NAC
ACK
UMTS HSDPA Uplink HS-DPCCH View for CQI feedback cycle 1
If the CQI feedback cycle is set to 1, each bar represents a 2 ms
HS-DPCCH subframe; 100 subframes are shown at a time.
The height of the bar indicates the CQI of this subframe. The color
depends on the feedback answer received from the mobile phone: ACK
(green), NACK (red) or no answer at all (DTX, yellow).
If the CQI feedback cycle is set to a value other than 1, the height of the
bar would be 0. However, a short bar is shown to indicate the ACK, NACK
or DTX message:
UMTS HSDPA Uplink HS-DPCCH View for CQI feedback cycle 4
The hybrid automatic repeat request (HARQ) is one of several new
methods used in HSDPA to implement higher data rates. The idea is to
keep the data received during the first transmission and to ask for
additional information in case any errors have been detected. Basically
there are two different types of HARQs:
Incremental redundancy: additional redundancy is added with each
retransmission
Chase combining: retransmission of the same coded block in each
retransmission
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The current status for each of the (up to eight) HARQ processes is shown
in the HSDPA HARQ Statistic View. A BLER >0 is clearly indicated by a
red bar from the left. (The HARQ process will be terminated then).
Alternatively green bars may be shown for the volume of new
transmissions.
UMTS HSDPA HARQ Statistic View
For each TTI subframe received, the complete demodulation and decoding
chain is shown in the HSDPA HS Decode Status View.
See also the R&S CMU300 "Realtime HS-SCCH Monitoring" section.
Each column represents one TTI subframe of 2 ms. A detailed view for
each subframe may be opened and pinpointed (see the "Sample 11" box,
which belongs to the subframe directly to the left of the pinpointed
window).
UMTS HSDPA HS Decode Status View
Each line shows the successful (green square) or unsuccessful (red
square) pass of each of the steps in the decoding chain:
Line 1: SCCH demodulation attempt
Line 2: SCCH decoding attempt
Line 3: CRC check of the data packet (yellow square denotes DTX)
The fourth line indicates whether the subframe contained a new
transmission or a retransmission. In the fifth line, the modulation scheme
used (16QAM or QPSK) is shown.
The next two lines provide information about the number of HS-PDSCH
codes used (in this subframe). One UE supports 5, 10 or 15 channels in
parallel (depending on the UE category).
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Finally the last line shows the initiated HARQ process for this subframe.
This number also defines the background color of the column.
Additionally, the pinpointed detail sample view shows the following three
values:
-
Code Group: code group indicator
-
Redundancy Version: Xrv includes the redundancy version parameters
r and s and the constellation version parameter b.
-
Transport Block Size: value of the transport block size (not explicitly
signaled, but decoded in accordance with the index value k t)
UMTS HSDPA Decode Statistic View
In the HSDPA Decode Statistic View, statistics are calculated once a
second to provide a quick overview of the transferred user data.
For each transport block size (TBS) captured, the following values are
shown (valid for all transport blocks of the same size):
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SB+: number of successfully decoded subblocks
-
SB++: number of successfully decoded subblocks that have been sent
more than once although the first transmission was already successful
(usually the reason is a missing ACK from the mobile phone)
-
SB-: number of subblocks that could not be decoded
-
SBLER: subblock error rate in % (calculated from the above values
SB+ and SB-)
-
BL+: number of successfully decoded blocks
-
BL-: number of blocks that could not be decoded
-
BLER: block error rate in % (calculated out of the above values BL+
and BL-)
-
#1: percentage of successfully decoded blocks at first transmission
-
#2: percentage of successfully decoded blocks at second transmission,
etc
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In the HSDPA MAC Configuration View, the MAC-hs configuration is
shown; some of the parameters depend on the test mobile phone used:
UMTS HSDPA MAC Configuration View
In the HSDPA MAC header view, the complete MAC-hs header
information is shown and decoded. The following parameters are listed:
-
Frame number (FN)
-
Version flag (VF)
-
Queue ID (ID) identifies the reordering queues in the receiver
-
Transmission sequence number (TSN) for reordering purposes to
support in-sequence delivery to higher layers
-
Size index identifier (SIDx) showing the size of the set of consecutive
MAC-d PDUs
-
Number of consecutive MAC-d PDUs of equal size (Nx)
UMTS HSDPA MAC Header View
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In the HSDPA MAC status view, the operator is able to check the
reordering sequence in the receiver in detail: received TSN, next expected
TSN and the window upper edge (WUE).
UMTS HSDPA MAC Status View
The main purpose for introducing HSDPA was to enable higher data rates
in the downlink.
In terms of quality of service, of greatest interest to the operator is the
resulting throughput on different layers – as a function of the existing radio
conditions. The following information is available in the HSDPA
Performance View, divided into five different 2D diagrams, all based on
the same timeline:
Requested throughput (requested from the mobile phone, calculated on
the basis of the CQI feedback)
-
Requested throughput (kbit/s)
-
Average CQI received from mobile phone
-
Share of QPSK/16QAM modulation (%)
-
Average number of HS-DSCH codes
The results are averaged over the number of subframes (100) shown in
the HSDPA HS-DPCCH View.
Throughput scheduled by the SCCH (throughput that in fact has been
assigned and reached)
-
SCCH throughput (kbit/s)
-
Share of QPSK/16QAM modulation (%)
-
Requested average number of HS-DSCH codes
The results are averaged over the number of subframes (100) shown in
the HSDPA HS-DPCCH View.
Delta throughput (scheduled throughput – requested throughput)
-
Delta throughput (kbit/s)
-
Delta share of QPSK/16QAM modulation (%)
-
Delta average number of HS-DSCH codes
The results are averaged over the number of subframes (100) shown in
the HSDPA HS-DPCCH View.
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HARQ throughput (similar to the scheduled throughput, but includes retransmissions)
-
HARQ throughput (kbit/s)
-
HARQ new transmission rate (%)
-
HARQ BLER (%)
RLC downlink throughput (RLC blocks that the mobile phone receives from
the network)
-
RLC downlink throughput (kbit/s)
-
RLC DL BLER (%)
Requested
throughput
Scheduled
SCCH
throughput
Delta
scheduled/
requested
throughput
HARQ
throughput
RLC DL
throughput
UMTS HSDPA Performance View
The graphical display of all of the above diagrams can be widely adapted
by the user.
The actual throughput on application layer is shown specifically for the
application (e.g. FTP download) in a separate window as part of the Data
Quality Analyzer module in R&S ROMES (see also the "Quality of Service
Measurements" section):
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QoS Throughput View
In addition to the completely new HSDPA-specific windows, other HSDPArelated information has been introduced in already existing windows.
For example, all HSDPA-specific layer 3 messages are shown and
completely decoded in the UMTS Layer 3 Message View.
HSDPAspecific
layer 3
information
Layer 3 messages and detail view
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Another example is the layer 1 rake finger data view, which provides the
HSDPA status for each of the mobile phone’s rake receiver fingers. The
bar shows the Ec/Io signal strength if it exceeds a selected minimum
strength.
UMTS Finger Data View
Finally, the following additional HSDPA-specific signals are provided by
R&S ROMES (i.e. the test device), which can be evaluated in user-defined
2D charts or alphanumeric views. It is also possible to export the following
values:
HSDPA Decode Summary
-
Decode Attempt Rate
-
Decode Success Rate
-
DSCH Passed Rate
-
DSCH Failed Rate
-
DSCH DTX Rate
-
Retransmission Rate
-
Max. Transport Block Size
-
Min. Transport Block Size
-
Average Transport Block Size
-
SCCH Max. # Codes
-
SCCH Min. # Codes
-
SCCH Avg. # Codes
-
SCCH Throughput When Served
-
SCCH Throughput When Scheduled
-
MAC Throughput
HSDPA CQI Statistics
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Time Span
-
Req. Min. CQI
-
Req. Max. CQI
-
Req. Min. # of Codes
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HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
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Req. Max. # of Codes
HSDPA Modulator Control Table
-
Start Global Sub. FN
-
No. Subframes
HSDPA SCCH Statistics
-
No. Subframes
-
No. Subframes SCCH Decoding Attempted
-
No. Subframes SCCH valid
-
HS-SCCH Success Rate
HSDPA DSCH HARQ Statistics
-
HARQ-Throughput
-
HARQ-Retransmission Rate
Coverage Measurements
The original purpose of a coverage measurement system (also referred to
as a mapping system) is to survey and record the existing coverage and its
characteristics during a drive test and to plot the relevant data onto a map.
Coverage measurements do not provide any HSDPA-specific data
(especially in idle mode). However, the recorded radio conditions have a
considerable influence on HSDPA performance. It is therefore wise to
check both aspects in parallel, i.e. to monitor the radio link parameters
during an HSDPA download and compare them with the achieved data
rates.
Coverage measurements may be performed by test mobile phones
performing calls (preferably HSDPA data calls) and by the R&S TSMU
radio network analyzer, which scans in parallel the radio environment – not
necessarily limited to the frequency in question, but the whole frequency
spectrum, incl. uplink.
Typically the Top N View provides a very good overview of the WCDMA
radio conditions:
PNS Top N View
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HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
The following parameters are shown for each CPICH in the Top N pool:
SC: scrambling code
Ec/Io: averaged energy per chip / total inband energy during one chip
SIR: signal to interference ratio
RSCP: received signal code power
ISCP: interference power
Ptotal: total average inband power
Frequency of the CPICH
Drift: mean time drift of P-CPICH signal
Dev. drift: 90% confidence interval width of mean time drift
Delay spread: RMS delay spread
HPP: hard pilot pollution
SPP: soft pilot pollution
CI: cell identity (with R&S TSMU BCH demodulation option)
MCC: mobile country code (with R&S TSMU BCH demodulation option)
MNC: mobile network code (with R&S TSMU BCH demodulation option)
Name of closest Node B using this SC (of Node B database if available)
As a typical output, the Ec/Io may be plotted onto a map; additionally the
best serving cell is indicated by a colored line:
Route Track View
If certain limits of e.g. Ec/Io or RSCP are of interest, it is possible to define
an "event", i.e. to indicate during measurement or replay the achievement
of a predefined threshold. Such indication may be visual or by an audio
signal, or both, depending on user definition. You can also differentiate
between a positive or negative slope.
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Rohde & Schwarz
HSDPA Network Optimization with the R&S CMU300 and
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Quality of Service Measurements
With the R&S ROMES DQA (Data Quality Analysis) module, which is fully
integrated into the R&S ROMES coverage measurement software, Rohde
& Schwarz offers a reliable tool for quality of service measurements for
packet-switched data with respect to the 3GPP/ETSI specification process.
For circuit-switched calls, the network quality analyzer (NQA) provides
ETSI-specified call parameters such as dropped call rate, for example.
The DQA can handle up to five mobile phones simultaneously. This makes
benchmarking of different networks under the same conditions very easy.
The DQA measurements are fully configurable since the DQA offers jobs
which can be combined in any order of sequence:
Connect to Network
Disconnect from Network
Ping
HTTP Download
FTP Download
FTP Upload
FTP Upload and Download simultaneously
UDP Download
UDP Upload and Download simultaneously
Web Browsing
E-mail Upload
E-mail Download
Each job is configured independently. For example, if five parallel
connections need to be tested, five connection jobs with up to five different
dialup connections have to be configured.
The DQA offers a variety of pre-defined views to show the results of the
different jobs and to present the automatically prepared statistics.
Examples of these views are the Qos Report View, which shows a statistic
of the connection jobs, or session-specific reports such as the FTP
Download Report View, for example.
For HSDPA, the preferred job would be a FTP or HTTP download. The
measurement results analyzed by the DQA are combined with the tracing
information of the HSDPA test mobile phone, e.g. application throughput in
comparison to requested or scheduled throughput (see also the UMTS
HSDPA Performance View and QoS Throughput View screenshots).
For further details of the DQA, please see reference [6].
In parallel the related general radio conditions are checked using the
R&S TSMU radio network analyzer, e.g. Ec/Io, RSCP, SC, etc (see the
"Coverage Measurements" section).
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HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
4 References
[1]
3GPP TS 25.141 Technical Specification, 3rd Generation
Partnership Project; Technical Specification Group Radio Access Network;
Base Station (BS) conformance testing (FDD) (Release 5)
[2]
Universal Radio Communication Tester R&S CMU300 Product
Brochure
[3]
Universal
Specifications
Radio
Communication
Tester
R&S
CMU300
[4]
R&S ROMES-US1 (R&S ESPI / R&S FSP) and R&S ROMES-US2
(R&S TSMU) Technical Information
[5]
Radio Network Analyzer R&S TSMU Data Sheet
[6]
R&S ROMES-Z6 (R&S ROMES DQA) and R&S ROMES-Z7 (VSQ
Analyzer) Technical Information
5 Abbreviations
1CM60_E.doc
3GPP
3rd Generation Partnership Project
ACLR
Adjacent Channel Leakage Ratio
BCH
Broadcast Channel
CDP
Code Domain Power
CPICH
Common Pilot Channel
DL
Downlink
Ec/Io
Energy per chip / Interference level
EVM
Error Vector Magnitude
FEC
Forward Error Correction
FDD
Frequency Division Duplex
HARQ
Hybrid Automatic Repeat Request
HSFN
High-Speed System Frame Number
HS-DPCCH
High-Speed Dedicated Physical Control Channel
HS-PDSCH
High-Speed Physical Downlink Shared Channel
HS-SCCH
High-Speed Shared Control Channel
HW
Hardware
GUI
Generic User Interface
Node B
WCDMA Base Station
OBW
Occupied Bandwidth
PCDEP
Peak Code Domain Error Power
PEP
Peak Envelope Power
RMC
Reference Measurement Channel
RNC
Radio Network Controller
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HSDPA Network Optimization with the R&S CMU300 and
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1CM60_E.doc
RSCP
Received Signal Code Power
SC
Scrambling Code
SEM
Spectrum Emission Mask
SFN
System Frame Number
SIB
System Information Block
SW
Software
TrCH
Transport Channel
TX
Transmitter
UE
User Equipment
UE-ID
User Equipment Identity
UL
Uplink
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Rohde & Schwarz
HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
6 Ordering Information
TYPE
Stock No.
R&S® CMU300
1100.0008.03
UNIVERSAL RADIO COMMUNICATION
TESTER FOR BTS TEST
R&S® CMU-B12
1100.5100.02
R&S® CMU-B78
1159.1800.02
HW OPTION FOR R&S CMU300:
REFERENCE OSCILLATOR OCXO, AGING
-8
3.5x10 /YEAR
HW OPTION FOR R&S CMU300: LAYER 1
BOARD FOR WCDMA DL RX AND UL TX
R&S® CMU-K72
1200.7603.03
SW OPTION FOR R&S CMU300: HS-SCH
MONITOR AND HS-DSCH THROUGHPUT
MEASUREMENT,
R&S CMU-K78 NECESSARY:
R&S® CMU-K75
1150.3200.02
SW OPTION FOR R&S CMU300:
WCDMA TX TEST (3GPP/FDD/DL)
R&S® CMU-K78
1157.4802.02
SW OPTION FOR R&S CMU300: BCH
SYNCHRONIZATION AND MONITORING
(3GPP FDD)
R&S® CMU-K79
1150.4407.02
SW OPTION FOR R&S CMU300: HSDPA TX
MEASUREMENTS (NON-SIGNALING,
3GPP/FDD/DL),
R&S CMU-K75 NECESSARY
TYPE
1CM60_E.doc
Designation
Stock No.
Designation
R&S® ROMES
1143.7991.30
R&S® ROMES-Z6
1143.8123.04
R&S® ROMES-UM1
1156.3031.04
R&S ROMES SOFTWARE MODULE
WCDMA - QUALCOMM MSM 62xx BASED
R&S® ROMES-UM4
1156.3031.06
R&S ROMES SOFTWARE EXTENSION
HSDPA – QUALCOMM MSM 6275 BASED
R&S® TSMU
1153.6000.02
RADIO NETWORK ANALYZER R&S TSMU
R&S® TSMU-K11
1153.4550.02
OPTION FOR R&S TSMU:
WCDMA PN-SCANNER
R&S® TSMU-K14
1153.4614.02
OPTION FOR R&S TSMU:
BCH DEMODULATOR
R&S® TSMU-Z1
1166.3786.02
POWER SUPPLY 230V FOR R&S TSMU
R&S® TSMU-Z2
1153.6700.02
RACK ADAPTER 19” FOR R&S TSMU
R&S® TSMU-Z3
1153.6900.02
INDOOR BACKPACK SYSTEM, FRAME
ND
WITH ACCU PACK, CHARGER, 2
BATTERY AND ACCESSORIES
R&S® TS51GA30
1090.7993.15
SYSTEM CASE PORTABLE
MEASUREMENT SYSTEM FOR R&S TSMU
AND UP TO 4 MOBILE PHONES
29
R&S ROMES DRIVE TEST SOFTWARE
PLATFORM WITH USB HARDLOCK INCL.
EXPORT
R&S ROMES SOFTWARE MODULE DQA
(DATA QUALITY ANALYZER)
Rohde & Schwarz
HSDPA Network Optimization with the R&S CMU300 and
R&S ROMES
.
.
.
.
.
ROHDE & SCHWARZ GmbH & Co. KG Mühldorfstraße 15 D-81671 München Postfach 80 14 69 D-81614 München Tel
.
.
(089) 4129 -0 Fax (089) 4129 - 13777 Internet: http://www.rohde-schwarz.com
This application note may only be used subject to observance of the conditions of use set forth in the download area of the
Rohde & Schwarz website.
1CM60_E.doc
30
Rohde & Schwarz
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